Houghton, MI 49931 Frost Dates
Frost dates for Houghton, MI, ZIP 49931
The last spring frost here typically falls around 05/17, about 262 days from today. The first fall frost typically arrives around 10/01, about 138 frost-free days later.
Houghton sits in USDA Zone 5b (-15 to -10°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 5b around Houghton has about 5 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
How much risk comes with planting early here
05/17 is the middle of 30 years of NOAA records, not a promise. Plant by 05/01 and you're betting against frost in roughly 9 years out of 10. 06/03 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Houghton compares
At roughly 138 frost-free days, Houghton places 37,374 of 40,283 ZIP codes in this dataset. Within MI, it ranks 922 of 1,153.
Learn more
local microclimates explains what one yard in Houghton can differ from the 49931 normal, and zone vs. frost date explains why Zone 5b and Houghton's frost date answer different questions.